


J'onn's Nemesis

by rowename



Category: Supergirl (TV 2015)
Genre: Cat is Thirsty, Cat is also kinky, F/F, Flashbacks, Humor, Telepathy
Language: English
Status: Completed
Published: 2019-10-27
Updated: 2019-10-27
Packaged: 2021-01-04 02:40:03
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,041
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21190199
Author URL: https://archiveofourown.org/users/rowename/pseuds/rowename
Summary: J’onn J’onzz has faced many trials. He has faced the White Martians in their ruthless war, he has faced power-mad Kryptonians, he has faced humanity at its worst, and has even faced his own brother.And yet nothing strikes quite so much fear and dread into his heart as four idle words from Kara.“Cat Grant’s coming back!”





	J'onn's Nemesis

**Author's Note:**

> I am half asleep and started having feelings over these two again, so here we are.

J’onn J’onzz has faced many trials. He has faced the White Martians in their ruthless war, he has faced power-mad Kryptonians, he has faced humanity at its worst, and has even faced his own brother.

And yet nothing strikes quite so much fear and dread into his heart as four idle words from Kara.

“Cat Grant’s coming back!”

* * *

It had started years ago. Almost as soon as Kara found out he was a shapeshifter, she’d asked his help to try and keep her identity a secret after Cat deduced it, by making it seem as though she and Supergirl were two distinct people.

He’d agreed without question. He could fly, it was easy for him to don the skirt and cape and look just like her. It was only ever going to be a quick meeting. He’d land, say hi to Cat, act like Kara, Kara would walk in, he’d fly off. Easy.

He got as far as landing before hearing Cat’s voice in his head. Like her speaking voice, her thoughts were clipped and precise, though unlike what she said aloud it was considerably less thought through.

_God, I never realized how short that skirt is. I wonder_… _Cat, no! Bad! She’s your assistant, you can’t just… well, technically _former _assistant. That’s different. There’s nothing wrong with just thinking. Maybe asking. _

J’onn coughed, trying to shake it off. He barely heard Cat’s actual words. Being a telepath, he’d heard people’s loud thoughts before even just walking down the street, though they were rarely quite so deafening.

Some people had things going on inside their head at a much greater intensity to the usual background hum of voices. Apparently, for Cat, she felt really strongly about… that.

Tune them out. Just focus on why he was there.

“Sorry to bother you Miss Grant,” he said in his best impression of Kara. “James Olsen said you wanted to see me, something about thinking your assistant was me?”

“Oh for god’s sake, are we going to keep playing this tiresome game?” Cat said.

_Lying to your boss probably deserves some kind of punishment. Maybe handcuffs. Would handcuffs even hold you? Hmm…_

“I told you it wasn’t a game, Miss Grant.”

J’onn breathed a sigh of relief at the distraction as Kara walked in. It took all his self-control to not wince and fly out the window there and then.

Cat did a double take, and for a moment her thoughts were silent.

“I’m afraid I can’t stay long,” J’onn said quickly. “There’s a lot of people out there that need help.” And a lot of people in here that really, really needed to stop thirsting for Kara.

Thankfully Cat did seem distracted by the sight of two of them. And then, a moment after J’onn felt a flicker of relief, she was distracted in the wrong way.

_Wait, two? Kara and Supergirl separately? You mean I could have them _both_? I normally don’t like being wrong but wow. _

J’onn went over to shake hands with Kara, helping along the charade, and glowering at her despite his Supergirl-esque words. He did _not_ need to hear any of this. This was her fault.

_And that means handcuffs would _definitely_ work on Kara. Ooh, the possibilities… I need a new paddle. Wasting Supergirl’s time like this, honestly, bad Kara. _

_No! Stop! She’s still your assistant!_

“Goodnight Miss Grant!” J’onn said very, very quickly. He just about avoided sprinting to the window.

Never again. Just, never again.

* * *

“You need to shapeshift into Kara,” Alex said.

“No,” J’onn said. “Absolutely not.”

Just then, Kara had been under the Black Mercy. She was trapped in a dream and, while they should be able to get her out eventually, it would take time. That was time she wasn’t spending being Kara Danvers, which meant Catco was missing her.

Which meant Cat.

“Her job’s important to her,” Alex said. “She can’t lose it lying around here. J’onn, please.”

J’onn hesitated. Kara and Alex reminded him of his daughters; it was so very hard to say no to them when they asked him for something. It was also very hard to put up with overhearing the blatant fantasizing of certain people.

Alex stared at him. J’onn cleared his throat before, reluctantly, speaking.

“Alright,” he said. “But you owe me.”

Besides, being Cat’s assistant didn’t necessitate spending all his time around her. He could drop off a coffee, run out of there as far as Kara’s legs could carry him, and then run errands and answer emails.

Hopefully Cat would be too distracted to keep thinking about Kara. It surely couldn’t be that bad again.

He’d taken one step into Cat’s office.

_Late. I really should ask if she’d mind me instituting corporal punishment. There’s nothing wrong with it if she agrees and god, what I wouldn’t give to have her over my knee and_-

J’onn coughed at the disturbingly vivid mental image Cat was broadcasting, only catching every other word she said. A list of demands, people to contact, something he was very eager to leave the office and do.

He left as soon as he could, taking Kara’s seat and quickly figuring out where everything was.

Typing emails. He could type emails, he ran a paramilitary organisation. Email addresses… there, and email programme there, so Cat wanted-

_You know that’s wrong. She’s still your assistant, and she really likes her job. Even if the power dynamic means it’s not appropriate to ask if she’d like to spend your next meeting on her knees under your desk. Mm, her mouth would be amazing-_

J’onn’s eyes widened, and he tried even harder to focus on the emails.

_She’s usually so obedient. If I asked her to keep her hands behind her back, just like she was, mm, on her knees using just her tongue and looking up at me, I’d let her keep those adorable glasses on. _

In H’ronmeer’s name, did Cat Grant do anything else with her day?! J’onn narrowly avoided accidentally crushing the keyboard. Focus on work, try to ignore the astonishingly loud fantasies Cat was having.

How did she managed to have such a normal-looking expression with all _that_ going on in her head?

He was so glad when she stopped having such detailed imaginings that he almost missed the content of her next few thoughts.

_Maybe she’d wear the costume… Honestly, does she really think that stunt with the duplicate proved she wasn’t Supergirl? I might have been, ahem, distracted, but I lived in _Metropolis_. I can think of about a dozen different shapeshifters and that’s not even getting onto technology. Maybe I should say something… _

_No, she can tell me when she’s ready. I’ll just see how easy it is to get a red sun-lamp installed in my bedroom. Just in case. _

Ok, that was… concerning. J’onn hesitated. While he was relieved Cat’s thoughts were on vaguely more appropriate topics, the fact someone else knew Kara’s identity was worrying.

Then again, it didn’t sound like Cat planned to do anything untoward, or at least nothing that was dangerous to Kara. It could be worse.

And, J’onn realised in a moment of panic, if Kara found out Cat suspected, she might want J’onn to help put on a double act _again_ to dissuade her. J’onn swallowed. No, maybe he’d just pretend he hadn’t heard that. He’d been pretending he hadn’t heard most of what Cat’s mind spouted anyway.

* * *

_Wow, my college ex is a shapeshifter, and Kara’s still so… I wonder if I could talk Liv into shifting into Supergirl, and see if Kara would want to-_

The less said about Cat’s thoughts during the Daxamite incident, the better. J’onn had heard she was present and promptly flown the other way.

* * *

“Cat Grant’s coming back!” Kara said brightly.

“When?!” J’onn said.

Kara blinked.

“Uh, in a couple of days,” Kara said. “Are you alright?”

“I’m going to Australia,” J’onn said. “Important DEO business. Don’t worry.”

Kara hesitated.

“You don’t work at the DEO any more,” she said.

Damn it. There went his usual excuse.

“I’m, uh, assisting,” J’onn said. He could get Alex to cover. She still owed him, both for helping out Kara and for the number of times Maggie had been at the DEO.

“Do you… need Supergirl?” she said.

“It’ll be fine,” J’onn said. “Keep Cat company. Let me know when she’s gone.”

“Uh…”

“That will be all,” J’onn said.

It would take a bit of rescheduling, but he could probably avoid being anywhere near National City when Cat was around. Technically speaking he did deserve a break.

Slightly bewildered, Kara left.

* * *

A day later and J’onn’s worst fear came to pass.

“J’onn! Cat came by early!” Kara said, happily skipping into his room.

“What?” he said with slowly dawning horror.

And then he heard it, the same blaring internal monologue he’d hoped never to overhear again, growing louder as Cat followed Kara down the street.

Don’t come in, don’t come in…

_Well she’s not your assistant now, there’s nothing wrong with asking. Though maybe see if you can get into your old office for… old time’s sake. _

J’onn swallowed. Cat walked through the doorway, coming up behind Kara with her usual disturbingly good poker face.

_I heard Supergirl had pants now. I hope I get to see that before I go, especially without the cape in the way, that’d be-_

“Hello,” J’onn said, slightly strained.

“One of Keira’s friends?” Cat said.

_Not that I minded the skirt, I’d still like to see that hiked up so I can reach, maybe she still has the old costume stored away somewhere. Mm, pants look good, but skirts give easy access, decisions, decisions…_

How was she pretending her focus was on introductions?! J’onn would almost have been impressed if not for the images she was broadcasting.

“And one of Supergirl’s,” J’onn said.

Kara looked at him strangely; Cat barely reacted. Maybe it was too subtle a hint. Or maybe Cat just had no shame about everything she was loudly thinking.

_I wonder if Kara’s going to be able to bring that second Supergirl back. With all the rumours around of her travelling around the mutiverse, it might actually be a second Kara. Imagine, both of them on their knees, taking turns- ooh! Better yet, both bent over my desk so _I_ can take turns-_

“One of her _telepathic _friends,” J’onn said pointedly.

Cat’s thoughts came to a screeching halt. J’onn was greeted with the rather rare sight of Cat Grant being lost for words.

“Oh,” Cat said. It lasted all of a second before she quickly schooled her expression. “That’s rather impolite.”

“You were shouting it,” J’onn said.

“If I’m going to think something, I’m going to commit,” Cat said. Her cheeks coloured slightly.

Kara looked between the two of them, bewildered.

“I’m leaving,” J’onn said. “Talk. Stop bottling it up. On behalf of every telepath on the continent, I implore you, do anything to stop yourself dwelling quite so much on all _that_.”

“Oh. Well. I- I think I’ll do that,” Cat said after a moment.

Breathing a sigh of relief, J’onn nonetheless hurried to the door, taking full advantage of the rare moment of silence.

* * *

A couple of days later, J’onn was flying back towards the city. Hopefully things would be sorted out now; best case, Cat would be gone, but failing that she wouldn’t need so much frustrated fantasizing if she knew for a fact it wouldn’t happen, or if it did happen and she worked it off.

Either way, he’d consider that a win. J’onn smiled, and had just about made it to the city’s airspace when-

_God, that’s _good_. I knew red sun lamps were a good investment. There’s a good girl, look at me, you’re doing so well, mm, show me how much you need it, scream for me, I can’t believe we were in the same office for years and I never did this once. _

_Ow, ow! Well there goes another desk. I can afford a new one, doesn’t matter. At least there’s always the wall. Oh, you want that do you? Naughty, that’s definitely earned another spanking. After. _

J’onn came to a sudden stop. Oh no.

He’d made it _worse_.


End file.
